1. Field of the Invention
The invention relates to coupling of optical fibers to optical networking components. In particular, the invention relates to increasing the efficiencies associated with coupling of an optical fiber and an optical component.
2. Background of the Invention
A variety of optical networking components includes one or more waveguides formed over a substrate. These waveguides are often coupled with optical fibers that carry light signals to and/or from the components. Reflection is known to occur at the intersection of an optical fiber and a waveguide. This reflection is a source of optical loss. Further, lasers are often the source of the light signal on an optical fiber. When a light signal from a laser is reflected at a component, the light signal can travel backward along the optical fiber and damage the laser.
An anti reflective coating is often positioned between the optical fiber and the component in order to reduce the level of optical loss. Anti reflective coatings are known to place stress on the waveguide. This stress can change the index of refection of the waveguide. The change in the index of refraction can reduce the quality of the component performance. Additionally, many anti reflective coatings do not adhere well to the component.
For the above reasons, there is a need for an improved method of coupling an optical fiber with an optical component.
The invention relates to a method of preparing an optical component for coupling with an optical fiber. The method includes determining a thickness of a buffer layer formed on the optical component. The method also includes forming an anti reflective coating adjacent to the buffer layer. The anti reflective coating is formed to a thickness selected in response to the determined buffer layer thickness.
Another embodiment of the method includes determining a thickness of an anti reflective coating formed on the optical component. The method also includes forming a buffer layer adjacent to the anti reflective coating. The buffer layer is formed to a thickness selected in response to the determined thickness of the anti reflective coating.
In some instances, the coefficient of thermal expansion of the buffer layer and the coefficient of thermal expansion of the anti reflective coating have opposing signs. In one embodiment, the buffer layer is formed so as to expand with increasing temperature and the anti reflective layer is formed so as to contract with increasing temperature.
The invention also relates to an optical component system. The optical component system has a waveguide with a waveguide facet. A buffer layer is positioned between the waveguide facet and the optical fiber. The buffer layer does not include SiO2. An anti reflective layer is positioned between the waveguide facet and the optical fiber.
In another embodiment of the optical component system, an optical fiber is coupled with an optical component, the optical component having a waveguide with a waveguide facet. A buffer layer is positioned between the waveguide facet and the optical fiber. The buffer layer has a thickness greater than 5 nm. The optical component system also includes an anti reflective layer positioned between the waveguide facet and the optical fiber.
The invention also relates to a plurality of optical component assemblies. The optical component assemblies include a plurality of optical components that are each coupled with one or more optical fibers. A buffer layer is positioned between the optical fibers and the optical components. At least a portion of the buffer layers have substantially different thickness. An anti reflective layer is positioned between the optical fibers and the optical components. The anti reflective coatings on optical components with different buffer layer thickness have a different thicknesses.